pkg-config trouble

I've run into some trouble with pkg-config and fontconfig on IRIX
when playing with X11_TYPE=modular. As you may know, IRIX doesn't
have transitive runtime linking, e.g. the whole tree of library
dependencies must be specified on the command line when linking.
Packages that use libtool deal with this quite well, since the .la
files tend to have all dependencies listed. The problem
I ran into concerns packages that use only pkg-config (such as
ghostscript).
Specifically, "pkg-config --libs fontconfig" returns:
-Wl,-R/usr/pkg/lib -L/usr/pkg/lib -lfontconfig
I believe the fontconfig.pc is wrong and should express need for
additional libraries, specifially -lexpat -liconv -lfreetype2 -lz.
What are the odds of breaking things on other platforms by adding this?
Also, how does this stuff interact with X11_TYPE=native?
I guess I would have to add for example -lfreetype2 directly, rather
than "Requires: freetype2", because builtin libraries
might not have .pc files? OTOH, a .pc faking framework has been
discussed before. If this is still a desirable feature I could
investigate it.
Your thoughts appreciated.
Cheers,
-Tobias